In the conventional art of this kind, Patent Document 1, for instance, discloses a technique as follows. A dozer frame lifted up/down via a dozer cylinder is pivotally supported to a traveling machine body via a horizontal shaft. The dozer frame pivotally supports a support body which is pivotable back and forth (“fore/aft direction” hereinafter) via an angle cylinder. The support body pivotally supports a blade via a fore/aft shaft, the blade being vertically pivotable via a tilt cylinder. A vertical shaft is disposed to extend through the fore/aft shaft at a fore/aft center portion of this fore/aft shaft and the tilt cylinder is disposed upwardly of this vertical shaft.
Further, in Patent Document 2, a fore/aft shaft is disposed at a position lower than the blade, a vertical shaft attached to the blade extends through a front end of this fore/aft shaft, and a tilt cylinder is disposed upwardly of the blade.                Patent Document 1: JP 2001-164597 A        Patent Document 2: JP 61-162639 A        